B K/mueller Inds(import) 521-403HN Black Pipe Cap 1/2 in

Product Description

The B K/MUELLER INDS(IMPORT) 521-403HN is a 1/2-inch black pipe cap designed to terminate or close off the end of a threaded black iron pipe run. It threads directly onto male-threaded pipe ends to create a secure, sealed closure. This type of fitting is a standard component in gas piping, compressed air, and industrial plumbing systems. Plumbers and pipefitters install these caps during pressure testing, system capping, or to close unused branch lines. The black iron finish is suitable for dry and gas-service applications where galvanized fittings are not required.

This pipe cap is used in residential and light commercial installations wherever a 1/2-inch threaded pipe end must be terminated. Common applications include capping unused gas line branches, closing off compressed air distribution lines, and sealing pipe ends during rough-in before final connections are made. Each package contains 25 caps, making this a practical supply for multi-point jobs or shop stock.

Key Features

• 1/2-inch threaded black iron pipe cap for standard NPT pipe ends
• Black iron finish suitable for gas and compressed air service
• Threads onto male-threaded pipe to create a sealed termination
• Sold in a 25-count package for job-site or shop stocking convenience
• Standard end-cap profile for straightforward installation and removal

Compatibility

Designed as an OEM-style replacement fitting compatible with standard 1/2-inch NPT threaded black iron pipe systems.

Installation Notes

Installation is performed by licensed plumbers or pipefitters following applicable local codes and IFGC requirements for gas piping. Shut off and depressurize the system before threading on the cap. Use appropriate pipe thread sealant or PTFE tape rated for the intended service medium. Do not overtighten, as black iron fittings can crack if excess torque is applied.